Before proceeding with installation, you need to have the
OCI instant clientlibraries and include files.
For example, you download the instantclient-basic-linux.x64-11.2.0.3.0.zip
library file, and the instantclient-sdk-linux.x64-11.2.0.3.0.zip SDK file,
and save them in your $HOME/Downloads directory. You would then uncompress
both files, and move the generated directory to your /opt path:

$ cd $HOME/Downloads

$ unzip instantclient-basic-linux.x64-11.2.0.3.0.zip

$ unzip instantclient-sdk-linux.x64-11.2.0.3.0.zip

$ sudo mv instantclient_11_2/ /opt/instantclient

After uncompressing you will probably need to create symbolink links:

$ cd /opt/instantclient

$ sudo ln -s libocci.so.11.1 libocci.so

$ sudo ln -s libclntsh.so.11.1 libclntsh.so

You will also need libaio. In Arch Linux this can easily be installed with:

Once you have the library and include files installed, and in order for the
installation script to locate them properly, you'll need to set the
OCI_INCLUDE_DIR and OCI_LIB_DIR environment variables. For example: